Aerodynamics for Students: A web textbook from the University of Sydney that covers undergraduate-level aerodynamics, fluid dynamics, aircraft performance and propulsion. Investigates the significance of pressure distribution on an aerodynamic body and the estimation of lift, drag and pitching moment of an aerofoil from the pressure around it in flight.

Beginner's Guide to Aeronautics: Prepared at NASA Glenn by the Learning Technologies Project (LTP) to provide background information on basic aerodynamics and propulsion for secondary math and science teachers. Includes interactive animated illustrations of many concepts.

NACA Technical Report Server: Searchable index of over 6,000 Research Reports, Technical Manuals, and Technical Notes produced by the National Advisory Committee for Aeronautics (NACA) between 1917 and 1958. Papers available as single-page GIF files or as complete-report PDF files.

Principles of Aeronautics: An online textbook discussing the basics of flight, drag and lift with content and lesson plans appropriate to all educational levels.

UIUC Airfoil Data Site: The University of Illinois at Urbana-Champaign airfoil database includes over 1,000 airfoils covering a wide range of applications, from low Reynolds number airfoils for UAVs and model aircraft to jet transports. Includes airfoil analysis resources.